I highly doubt their attitude was genuine. Why didn't they help at the beginning of the war rather than helping in the end?
Back then, India always saw us as threat. If war broke out which it eventually did, India would have to fight 2 fronts rather than deal with 1. It was in India's interest that BD broke out of Pakistan.
India, US they are all the same. They will only join up if there is something in it for them.
Obviously, India thought that by helping BD, we would be forever their "puppet" state, just like Australia is to US after saving their a$$ from Japan in WW2. Well they were wrong, which is why they are having these debates. Whats the point of helping us if we become more closer to Pakistan in the end than our actual aide?
To sum it up, India had 2 reason to helping us out:
1) To avoid war on 2 front.
2) By helping us, they would have a cooperative "sattelite" state under their sphere of influence.
While they achieved objective (1), they didnt achieve (2). Humanitarian feelings was definitely not the reason.